landing page as my homepage

Hello,

I’m building a website site for members only, completely private, no free membership. I don’t want to the visitors to see the post or the navigation bar.

I’d like to create a landing page as my homepage with a description of the site, the advantage, my bio, testimonials, the price and a subscribe button.

I want the rest of the website should be behind this page accessible after login.

How can I do that? Is there a plugin?

Thanks!

Anne